[Amps] IM distortion and such

[Tom W8JI]

>> In my experience, VHF instability is independent of 
>> loading
>> since VHF never gets through a low pass Pi tank circuit.
>
> Another canard ... VHF doesn't need to get through the 
> tank
> circuit.  The damage is almost always at the input (tune 
> padder
> and/or 10/15 meter coil contacts) that is the point that 
> RF voltage
> is the highest.  Remember the output tank transforms a 
> High-Z tube
> to a low-Z antenna ... high-Z is high voltage/low current.

It can be proven beyond a doubt if it is possible to get a 
VHF arc in any amplifier.

It only takes a little logical thinking, and a little test 
equipment to measure voltage levels through the system at 
various frequencies.

My conclusion is this VHF arcing stuff is way overblown and 
the data alleged to support it is seriously flawed in many 
ways.

73 Tom